A modular jack incorporating a varistor. The varistor reduces noise and surge (abnormal voltage) entering the modular jack, and thereby an electronic appliance such as a telephone connected with the modular jack is not affected by the noise and surge. The varistor is electrically connected between at least a pair of contact leads. Alternatively the varistor is electrically connected between the pair of contact leads and a grounding terminal. Further, the modular jack incorporates a common mode choke coil so as to obtain a common mode noise reduction effect.
